| 摘要 |
A riser assembly (106, figure 1), particularly for managed pressure drilling, includes a rotating control device RCD 200 (112, figure 1) connected between an upper portion (110, figure 1) and a lower portion (116, figure 1) of the riser assembly. The RCD comprises a housing 202, a bearing package 204 and a packing element 206. Bearing package includes an outer hosing 220 and locking assemblies 222 and 224. Packing element is engaged within bearing 204 and includes stripper rubber 240 and housing 242 and isolates an annulus of the lower portion from the upper portion when a drill string is engaged. The bearing package and packing element are retrieved, replaced and installed by means of a tool (570, 770 and 970, figs 6, 8 and 10) run in through the upper portion without necessitating disassembly and reassembly of the riser. The packing element may also be replaced without de-pressurizing the annulus of the riser assembly. |
